1. Field of the Invention
The present invention relates to a head-protecting airbag device having an airbag that is adapted to be stored at upper peripheries of windows of a vehicle in a vehicle interior for deployment over the windows and includes inflatable portions for covering inboard sides of the windows and a pillar disposed between the windows.
2. Description of Related Art
WO 2013/018781 A discloses a head-protecting airbag device having an airbag that covers inboard sides of front and rear windows of a vehicle as well as an inboard side of a middle pillar disposed between the windows upon deployment. In this airbag, a pillar cover portion for covering the middle pillar takes in an inflation gas from a front window cover portion for covering a window located in front of the middle pillar.
However, the pillar cover portion takes in an inflation gas also from a rear window covering portion for covering a window located at the rear of the middle pillar. Further, the pillar cover portion also includes an outlet port which forwards an inflation gas to an inflatable portion located in front of the front window covering portion.
With this configuration, with an inflation gas from the front window covering portion as well as from the rear window covering portion, the pillar cover portion may inflate almost simultaneously with the front window cover portion. In such an instance, if an inflated portion contacts a seatback of a seat located at an inboard side of the middle pillar, the pillar cover portion may fail to deploy to the lower edge but complete inflation at a side of the seat, which may further cause an incomplete deployment of the front window cover portion and rear window cover portion.
JP2009-227161 A also describes an airbag provided with a pillar cover portion. The pillar cover portion serves as a secondary inflatable portion which helps prevent an abrupt boost of an internal pressure in a front window cover portion as a primary inflatable portion.
Since this pillar cover portion takes in an inflation gas only from the front window cover portion, the pillar cover portion inflates only after the front window cover portion starts to inflate. Accordingly, the airbag easily unfolds to the lower edge in an initial stage of airbag deployment between a middle pillar and a seat located at an inboard side of the middle pillar. However, since the pillar cover portion is formed into a rectangular cell elongated in an up and down direction as viewed from a vehicle interior, if it inflates while unfolding downward and contacts a seatback, the pillar cover portion may fail to deploy to the lower edge but complete inflation at a side of the seat, which may further cause an incomplete deployment of the front window cover portion and rear window cover portion as the above.